• Title/Summary/Keyword: etoposide

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HS 1-Associated Protein X-1 Is Cleaved by Caspase-3 During Apoptosis

  • Lee, Ah Young;Lee, Yoora;Park, Yun Kyung;Bae, Kwang-Hee;Cho, Sayeon;Lee, Do Hee;Park, Byoung Chul;Kang, Sunghyun;Park, Sung Goo
    • Molecules and Cells
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    • v.25 no.1
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    • pp.86-90
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    • 2008
  • Caspase-3 (CASP3) plays a key role in apoptosis. In this study, HAX-1 was identified as a new substrate of CASP3 during apoptosis. HAX-1 was cleaved by CASP3 during etoposide-(ETO) induced apoptosis, and this event was inhibited by a CASP3-specific inhibitor. The cleavage site of HAX-1, at $Asp^{127}$, was located using N-terminal amino acid sequencing of in vitro cleavage products of recombinant HAX-1. Overexpression of HAX-1 inhibited ETO-induced apoptotic cell death. It also inhibited CASP3 activity. Together, these results suggest that HAX-1, a substrate of CASP3, inhibits the apoptotic process by inhibiting CASP3 activity.

The Effects of five kinds of Artemisia capillaris $T_{HUNB}$ fractions on Cell Viability, Cell Cycle Progression and Fas-mediated Apoptosis of HepG2 Cells (인진(茵陳)분획물이 간세포활성, 세포주기 및 Fas-mediated Apoptosis에 미치는 영향)

  • Kim, Young-Chul;Lee, Jang-Hoon;Woo, Hong-Jung;Yi, Jong-Hoon
    • The Journal of Internal Korean Medicine
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    • v.21 no.3
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    • pp.363-368
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    • 2000
  • Objective : This study was carried out to examine the effect of five fractions of an aqueous extract from Artemisia capillaris $T_{HUNB}$. Methods : The queous extract from Artemisia capillaris $T_{HUNB}$. was fractionized into 5 kinds of material. We observed the effect of each fractions on etoposide-induced apoptosis, cell viability, cell cycle progression and mRNA expression of apoptosis-related genes in human hepatocyte cell line HepG2. Results and Conclusions : The data shows that butanol fraction of Artemisia capillaris $T_{HUNB}$. has no relation with cell cycle, however, it inhibits apoptosis significantly and the action may be due to the suppression of Fas and Sax genes and activation of Bcl-2 gene.

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Molecular Biological Study of The Effects of Gilgyung-Tang(GGT) on Cellular Proliferation and Viability of Normal Human Lung Fibriblast Cell (길경탕(桔梗湯)이 인체(人體) 폐세포(肺細胞)에 미치는 영향(影響)에 관(關)한 분자생물학적(分子生物學的) 연구(硏究))

  • Rhee, Hyung-Koo
    • The Journal of Korean Medicine
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    • v.20 no.2
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    • pp.88-97
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    • 1999
  • To characterize the effects of Gilgyung-Tang(GGT) on cellular proliferation and viability of normal lung fibroblast cells, we examined the cell cycle progression and cell cycle-related gene expression in T3891 using a flow cytometry and a quantitative RT-PCR analysis. 1. The significant surpression effect of cellular proliferations of GGT was observed in proportion to a certain concentration and time. 2. GGT was identified to induce apoptotic death of damaged cells by treatment with a DNA-damage agent and etoposide, while it stimulated the recovery of cellular viability of normal cells. 3 The significant reductions of mRNA expression of PCAN, c-Fos treated by GGT were observed. 4. The significant inductions of mRNA expression of p53, CDKN1. Gadd45 treated by GGT were observed. 5. The apoptosis caused by the reduction of Bcl-2 genes was significant and the Bax genes were increased. but the amount of Fas genes were not changed. These results strongly suggest that GGT triggers arrest of the cell cycle at G1 phase, and thus causes an inhibition of cellular proliferation of human normal lung cells through the transcriptional up-regulation of cell cycle inhibitory genes and down-regulation of induction of cell cycle stimulating genes respectably.

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Metastatic Brain Neuroendocrine Tumor Originating from the Liver

  • Lee, Guk Jin;Jo, Kwang Wook;Kim, Jeana;Park, Il Young
    • Journal of Korean Neurosurgical Society
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    • v.58 no.6
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    • pp.550-553
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    • 2015
  • A 67-year-old male presented with left temporal hemianopsia and left hemiparesis. A contrast-enhanced magnetic resonance image revealed a $4.5{\times}3.5{\times}5.0cm$ rim-enhancing mass with central necrosis and associated edema located in the left occipital lobe. Of positron emission tomography and abdominal computed tomography, a 9-cm mass with poor enhancement was found in the right hepatic lobe. Craniotomy and right hemihepatectomy was performed. The resected specimen showed histological features and immunochemical staining consistent with a metastatic neuroendocrine tumor (NET). Four months later, the tumors recurred in the brain, liverand spinal cord. Palliative chemotherapy with etoposide and cisplatin led to complete remission of recurred lesions, but the patient died for pneumonia. This is the first case of a metastatic brain NET originating from the liver. If the metastatic NET of brain is suspicious, investigation for primary lesion should be considered including liver.

Knockdown of RCAN1.4 Increases Susceptibility to FAS-mediated and DNA-damage-induced Apoptosis by Upregulation of p53 Expression

  • Kim, Young-Sun;Lee, Hong-Joon;Jang, Cho-Rong;Kim, Ho-Shik;Cho, Young-Jin
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.6
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    • pp.483-489
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    • 2009
  • Despite the potential importance of the human regulator of calcineurin 1 (RCAN-1) gene in the modulation of cell survival under stress, little is known about its role in death-inducing signal pathways. In this study, we addressed the effects of RCAN1.4 knockdown on cellular susceptibility to apoptosis and the activation of death pathway proteins. Transfection of siRNAs against RCAN1.4 resulted in enhanced Fas- and etoposide-induced apoptosis, which was associated with increased expression and translocation of Bax to mitochondria. Our results suggest that enhanced expression and activation of p53 was responsible for the upregulation of Bax and the increased sensitivity to apoptosis, which could be reversed by p53 knockdown. To explain the observed upregulation of p53, we propose a downregulation of the ubiquitin ligase HDM2, probably translationally. These findings show the importance of appropriate RCAN1.4 expression in the modulation of cell survival and reveal a link between RCAN1.4 and p53.

Cytotoxicity and DNA Topoisomerases Inhibitory Activity of Constituents from the Sclerotium of Poria cocos

  • Li, Gao;Xu, Ming-Lu;Lee, Chong-Soon;Woo, Mi-Hee;Chang, Hyun-Wook;Son, Jong-Keun
    • Archives of Pharmacal Research
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    • v.27 no.8
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    • pp.829-833
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    • 2004
  • The bioactivity-guided fractionation of the methylene chloride extract of the sclerotium of Poria cocos led to the isolation of (S)-(+)-turmerone (1), ergosterol peroxide (2), polyporenic acid C (3), dehydropachymic acid (4), pachymic acid (5), and tumulosic acid (6). Compounds 4-6 exhibited moderate cytotoxicities, with $IC_{50}$ values of 20.5, 29.1, and $10.4{\;}\mu\textrm{m}$, respectively, against a human colon carcinoma cell line. However, 3-6 not only showed inhibitory activities as potent as etoposide used as a positive control on DNA topoisomerase II (36.1, 36.2, 43.9 and 66.7% inhibition at a concentration of $20{\;}\mu\textrm{m}$, respectively), but also inhibition of DNA topoisomerase I (55.8, 60.7, 43.5, and 83.3% inhibition at a concentration of $100{\;}\mu\textrm{m}$, respec-tively).

Synthesis and Biological Properties of Luotonin A Derivatives

  • Rahman, A. F. M. Motiur;Kim, Dong-Hyeon;Liang, Jing-Lu;Lee, Eung-Seok;Na, Young-Hwa;Jun, Kyu-Yeon;Kwon, Young-Joo;Jahng, Yurng-Dong
    • Bulletin of the Korean Chemical Society
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    • v.29 no.10
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    • pp.1988-1992
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    • 2008
  • A series of new derivatives on the ring A of luotonin A were prepared by Friedländer condensation of 6,7,8,10- tetrahydropyrrolo[2,1-b]quinazoline-6,10-dione and suitably substituted 2-aminobenzaldehydes and 2- aminoacetophenones. Their inhibitory activities on topoisomerases and cytotoxicities against selected human cancer cell lines were evaluated. Among the compounds tested, 8-fluoroluotonin A showed similar inhibitory activity on topoisomerase I comparable to camptothecin while luotonin A and 9-hydroxyluotonin A showed 1.37 and 0.94 times stronger inhibitory activity, respectively, on topoisomerase II compared to etoposide. Some derivatives of luotonin A showed moderate cytotoxicity. The possible relationship between the inhibitory activity on Topo II and the cytotoxicity of luotonin A and its analogues, thus, cannot be ruled out.

Clinical Study on Carboplatin for Treating Pediatric Patients with Wilms Tumors

  • Zhang, Yong;Sun, Ling-Li;Li, Tao;Sun, Hui;Mao, Guo-Jia
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.17
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    • pp.7277-7280
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    • 2014
  • This analysis was conducted to evaluate the efficacy and safety of carboplatin based chemotherapy in treating pediatric patients with Wilms tumors. Methods: Clinical studies evaluating the efficacy and safety of carboplatin based regimens on response and safety for pediatric patients with Wilms tumors were identified using a predefined search strategy. Pooled response rates (RRs) of treatment were calculated. Results: In carboplatin based regimens, 4 clinical studies which including 127 patients with advanced Wilms tumors were considered eligible for inclusion. With this carboplatin based chemotherapy, 2 clinical studies included carboplatin, ifosfamide and etoposide. Systemic analysis suggested that, in all patients, the pooled PR was 64.5% (82/127) in carboplatin based regimens. Thrombocytopenia and leukocytopenia were the main side effects. No grade III or IV renal or liver toxicity was observed. No treatment related death occurred with carboplatin based treatment. Conclusion: This systemic analysis suggests that carboplatine based regimens are associated with a reasonable response rate and accepted toxicities for treating pediatric patients with Wilms tumors.

Effects of Quinolone Derivatives on Topoisomerase II (퀴놀론 유도체의 Topoisomerase II에 대한 효과)

  • Yeon, Seung-Woo;Paek, Nam-Soo;Kim, Tae-Han;Kim, Kee-Won
    • YAKHAK HOEJI
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    • v.40 no.6
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    • pp.697-704
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    • 1996
  • Quinolone derivatives, SJ5b (ethyl 5,12-dihydro-5-dihydro-5-oxobenzoxazolo[3,2-a]quinoline-6-carboxylate) and SQ7b (3-fluoro-2-(4-methylpiperazin-1-yl)-5.12-dihydro-5-oxobenzoxa zolo[3,2-a]quinoloine carboxylic acid) showed in vitro cytotoxicities against various tumor cell lines. SJ5b and SQ7b completely inhibited the DNA relaxation activities of human placental topoisomerase II at the concentration of 15.63 and 1.95 ${\mu}$g/ml, respectively. However, unlike etoposide which stabilize the topoisomerase II-DNA complex, SQ7b did not cause topoisomerase II-mediated DNA cleavage and SJ5b weakly stabilized the topoisomerase II-DNA cleavable complex. Through both experiments. DNA relaxation assay by the increment of topoisomerase II concentration and DNA unwinding assay, it was shown that SJ5b and SQ7b did not interact with topoisomerase II itself but bound to DNA. Therefore, it was concluded that DNA binding of SJ5b and SQ7b caused the inhibition of topoisomerase II related to DNA relaxation but no or very weak stabilization of topoisomerase II-DNA cleavable complex. In addition, SJ5b and SQ7b prevented whole cell nucleic acid syntheses in HL60 cells.

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Surgery of Advanced Esophageal Cancer after Chemotherapy (선행화학요법을 시행한 식도암 환자의 외과적 고찰)

  • 임수빈;이종목
    • Journal of Chest Surgery
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    • v.29 no.5
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    • pp.536-541
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    • 1996
  • Between June 1988 and June 1994, twenty five patients with locAlly advanced esophageal carcinoma received preoperative chemotherapy (Cisplatln, 5-Fluorouracil with or without Etoposide) and followed by resection. All patients had clinical evidence of airway involvement or distant Iymphnode involve- ment (M 1 Iymphnode) on bronchoscopy or computed tomographic scans. The major response rate to chemotherapy decided by the postoperative stage was 48% (12125). The resection rate was 92% (23/25) with overall complete resection rate of 72% (18125). Two patients had exploratory laparotomy (thorn- cotomy) only. Thirteen patients had esophagogastrostomy with a combined abdominl and Rt. thoracic approach (Ivor Lewis operation), slx pAtients had transhiatal esophagectomy, four patients had esophagogastrostomy with a combined Rt. thoracotonly & abdominal, cervical approach. There were three postoperative deaths (12%). Follow-up duration was between 3.3 months to 65 months. Median survival ime of resected patients except hospital death was 14.8 months. Actuarial survival at 12, 24 months was 72.9%, 26.2%. Signifi- cant better survival was associated with responder group (postoperative stage less than lIB) (P=0.029). These results demonstrate that 1) Preoperative Cisplatin based combined chemotherapy Produce high response rate, 2) High complete resection rate with acceptable mortality rate occur after preoperative chemotherapy, 3) Better surviL dl can be anticipated if complete resection performed after major re- sponse to preoperative chemotherapy.

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